Waste batteries are called, for example, wastes generated when the life-spans of primary batteries used as power sources for various electronic devices including remote controllers, calculators, radios, electronic clocks, cassettes, toys, and the like and rechargeable secondary batteries including batteries for mobile phones, notebooks, and automobiles have ended.
The waste batteries include valuable metals including silver, cobalt, nickel, zinc, manganese, lithium, copper, and the like. Therefore, in order to efficiently recycle finite resources, development of technology for recovering the valuable metals from the waste batteries is required. In addition, since KOH, NH4Cl, lithium salt, H2SO4, and the like are used as electrolytes in the waste batteries in addition to lead, cadmium, mercury, and the like which are hazardous metals, it is necessary to develop recycling technology in consideration of environmental impacts.
In waste battery recycling technologies developed in the related art, a process of classifying collected waste batteries by respective batteries, such as the primary battery and the secondary battery, a process of crushing the classified waste batteries, a process of classifying the crushed materials by a sieve, and a process for sorting metals to be recovered and residues are performed as a pretreatment process.
However, in this related art, the processes of classifying the collected waste batteries by the batteries of the primary cell and the secondary battery and crushing the classified waste batteries are required. In the process of directly crushing the waste batteries, there is a risk of explosion of the battery and further, generated electrolytes and gas are exposed to the atmosphere, thereby giving a great burden to an environment.
In view of this, a method for recovering valuable metals from waste batteries by a method disclosed in a prior art document has been provided, but here, work is performed by inputting only a predetermined amount of waste batteries into a reaction reservoir at a time. Therefore, there is a problem that it is difficult to mass-treat the waste batteries in the pretreatment process of the waste batteries because the amount of the waste batteries which may be treated at a time is relatively small.
In addition, even in the related art using the reaction reservoir, since there is still the risk of explosion inside the reaction reservoir, stability is lowered and there is also a problem in that it is inconvenient to take out a treated material from the reaction reservoir to the outside after heat treatment.